Want this question answered?
Be notified when an answer is posted
Chat with our AI personalities
You work it out on paper or just use a calculator
Any +++ Strictly speaking, it is ADD. The word 'sum' is used colloquially for any simple arithmetical calculation, but in mathematics a 'sum' is properly the result of adding two or more numbers.
You can use the formula for the sum of an arithmetic series to calculate that quickly. (Of course, you can also type the numbers into Excel, and get the sum - but that doesn't scale well - e.g., it won't work well if you are then asked, for instance, to get the sum of the first million even numbers.)
To find the sum of integers, you use addition.To find the difference, you use subtraction.
the answers -20